1. Technical Field
The field of this invention is polysulfur-containing polymeric ester compositions and their polymers.
2. Background of the Invention
Despite the mature nature of the field of polymers, there remain many opportunities to create polymers having novel properties and applications. Polymers may be divided into addition polymers and condensation polymers. Among the condensation polymers are polyesters, polyethers, polyurethanes, polyamines, and polyanhydrides. These polymers find wide application in areas of molded products, lubricants, sealants, coatings, paints, elastomers, films, fibers, elastomers and other formulations. Their properties vary widely depending upon the functional groups employed, both as to nature and diversity, the backbone units, the functionalities in the backbone, the molecular weight and homogeneity of molecular weight range of the polymeric molecules, and the like. Because of the great diversity of properties of the polymers, there can be numerous customized applications for the polymers, where the properties of the polymers are customized to a particular need.
Polymers containing polythioalkyl groups have not found extensive employment in the polymeric field, with the exception of the Thiokol® polymers that currently are not widely used due to environmental concerns. Yet, the presence of sulfur in the polymers can have desirable properties. Some polymeric products containing polysulfide linkages have been reported for a variety of purposes, such as polymers having disulfide and ether groups, disulfide and carbamate groups, and disulfide and acetal groups in the polymer backbone. There have been reports of other polymeric compositions, where the disulfide is in a side chain of the polymer, as in addition polymers of acrylics. While specific compounds having sulfides having greater than one sulfur are disclosed in the literature, for the most part they are not exemplified in the experimental work. Specifically, there have been no reports of polymers employing a monomeric unit of a polysulfide functionality in the backbone and formed from a combination of a polysulfide-containing diol and a dibasic acid.
Relevant Literature
Ethers of di(hydroxyethyl)sulfide and -disulfide are reported in U.S. Pat. No. 2,582,605. Polymers of alkyldisulfides terminating in hydroxyl groups and further reacted with polyurethanes are reported in U.S. Pat. No. 3,386,963. Polymers of polymerized thiodiglycol reacted to provide terminal halide groups which are then further reacted with sodium polysulfide to form a latex dispersion are reported in U.S. Pat. No. 4,124,645. Polymers of polymerized sulfide and polysufide glycols terminated with mercaptans are reported in U.S. Pat. No. 4,764,299. U.S. Pat. No. 6,383,324 reports the polymerization of a “randomly copolymeric polyacetal of a dithiodialkylene glycol” with polyisocyantes. Sulfur substituted acrylic polymers are reported in U.S. Pat. Nos. 4,131,716 and 6,114,485.